A big part of producing theatre is controlling the cost – but you never want that to be on anyone else's mind but yours (and certainly not the audience's). As the late Ken Russell used to say, he never heard anyone come out of a movie saying: "What I loved about that film is that the producer brought it in on budget."

But, all the same, waste is stupid, particularly because it also has an effect on the environment. So the idea I had was: if we make a show without taking any energy from the national grid, what would happen? And what lessons would we learn that we could apply to all our work? By its very nature, climate change is a global problem, the scale of the challenge is huge, and any impact we in the theatre sector have will be small, but it seemed equally stupid to ignore the problem; more, it has been a fascinating problem to think about.

One obvious and practical energy-saving route affects something that all performance thrives on: light. The National Theatre and technology company Philips has been exploring ways of illuminating a stage with equal brightness but less electricity, as well as various energy-saving measures elsewhere in the building. But by focusing on related questions, by forcing a greater awareness of what we destroy in order to create, could we at the Young Vic achieve a better sense of what the issues really are, and how they affect the theatre that we all create?

The name arrived in an instant: Classics for a New Climate. We wouldn't want to produce specially commissioned plays or meditations on ecology. Rather, we would want to think how to achieve maximum pleasure and insight from existing repertoire, while also thinking about how it could involve less carbon. We briefly enjoyed fantasising about employing teams of bicyclists on the roof, pumping away to generate electricity to power our lamps. We considered performing only during the hours of daylight. And so on.

Director Natalie Abrahami suggested that Patrick Marber's After Miss Julie should be our first New Climate Classic – not only because she loves it but because the play's journey from dusk to dawn provides a neat challenge for an energy-low production style. Moreover, Marber's ingenious rethinking of the Strindberg original is set in the austerity Britain of 1945: they, too, had to make a little go a long way. But quickly Abrahami and her designers, Patrick Burnier and Oliver Fenwick, realised that if we were going to go for zero energy, all their energies would go into realising that aim, leaving none for the show itself. So we had to make some compromises. This project is, after all, about finding a lower-carbon way of working, as well as about finding techniques we can develop in future.

A good goal seemed to be to use 60% less measurable greenhouse gas emissions than we'd used on previous shows in our small studio space, the Maria. This would be in tune with the London mayor's 2008 Green Theatre Plan, which calls for a reduction of that scale by 2025. For the last four comparable shows in the Maria – in terms of budget, cast size and scale – vans and lorries drove between 300 and 3,000 miles to deliver sets and equipment, resulting in an average of 790kg CO2e per production. Pleasingly, After Miss Julie's production, transport has seen an 80% improvement, at just 190kg CO2e. Most of the props on stage come either from previous shows, sourced locally from markets or made from secondhand or recycled material. The costumes have been refashioned from vintage clothing or 1940s fabric found in local markets: something that saves not only on material (with all its embedded carbon footprint) but is arguably more authentic.

This, though, is just the start. In order to have a good chance of learning where to go next, we need to examine every part of the process of making a show: how we reuse and recycle elements of the set, how we can get rid of paper tickets, how we can log – and reduce the footprint of – everyone's travel to and from work each day. As well as offering audiences the chance to see a first-rate cast in a terrific play, this is what the whole idea had been about in the first place.